I must confess, I may have a vested interest on this one: I saw this play in a production starring a friend as the lead. However, I think I can say fairly objectively that not only his performance but the play itself was staggering.

It’s a recipe for an unusual night out: 17-year-old Alan Strang has blinded six horses with a metal spike, and the audience must follow psychiatrist Martin Dysart’s attempts to understand and help him. What this premise does not prepare you for is the masterwork that is Shaffer’s psychological exploration of religion and sexuality. The journey of Alan’s life, recollected piece by piece as he slowly grows to trust Dysart, startlingly reveals the agony and passion of faith and sex in the modern, ‘enlightened’ and above all uncertain world of today; it is as accurate to now as it was to the 1970s.

Equus is a play that reminds us why some clichés became clichés. Philosophical ideas communicated through a story of the unravelling of a troubled mind and its troubled history is a format that has been overdone. Narrative examination of a character’s influences and personal history to explain their crime, framed within a psychiatric setting, has likewise been employed far too many times. But in Equus it all hangs together perfectly. It might be a frame narrative within a frame narrative, but only this structure enables Shaffer to fully explore the viewpoints of the various different characters. And fundamentally, the troubled history of the mind can indeed be moving, devastating and catastrophic, and in Equus Shaffer shows us this without being cheesy or over the top.

The strongest criticism I can make of this play is that it is somewhat inaccessible in parts, since all but one of the characters are difficult to like or understand. However, that is as it should be. Dysart’s pretentions, Jill’s quirks, Mr Strang’s hypocrisy and Mrs Strang’s selfishness are all crucial to the relationships they have with Alan, and in the end the audience need only understand him and his experiences, something Shaffer ensures we do.

A secularist society, politically, religiously and sexually open-minded to a degree unthinkable for most of history, while of course desirable, brings its own difficulties. The modern teenager, faced with wildly conflicting influences and censorships, but not unswervingly forced in one straight line, must rewrite the rulebook for him or herself. We are not only entitled to our views, we are socially required to have them, to select them, mould them or invent them entirely.

Alan Strang’s story is an extreme, but horribly plausible, example of a plight I fear many will find themselves in. Faced with a thousand different political debates and affiliations, a thousands religions and philosophies and a thousand possible sexualities, with everything from John Donne’s sadomasochistic addresses to God to vicious homophobia and political extremism readily available online, we find ourselves in turmoil perhaps even more than Alan. Alan’s passion, in every sense of the word, is a shockingly revealing portrayal of a torturous issue.